A comparison of the nutrient content of uncooked and cooked lean from New Zealand beef and lamb

The composition in terms of proximate analysis, cholesterol, vitamins, minerals, and fatty acids of the lean tissue of 17 beef cuts and 18 lamb cuts was determined on within-cut composite samples (each containing lean tissue from at least 7 animals), following the knife-separation of raw and cooked cuts into lean, fat, and bone. Composite lean samples for 4 beef cuts and 4 lamb cuts were also analysed for amino-acid composition. For analysis, different cuts were the experimental unit as individual animal data were not available. The composition of lean from beef and lamb was shown to be highly desirable with a high nutrient density (mg/kJ) for many nutrients. Although lean from beef and lamb were very similar in many respects, several significant differences were detected. Changes in composition with cooking were largely eliminated when considered on a dry-matter basis, but proportions of the n-3 and n-6 polyunsaturated fatty acids increased with cooking (P < 0.05). The amino acid composition was similar for lean from beef and lamb but showed small deviations from recommended patterns for human nutrition with branched chain amino acids being limiting.     

Vitamin supplements among women with adenomatous polyps and cancer of the colon

Chemoprevention of various epithelial cancers with vitamins or minerals has been the subject of multiple intervention trials to assess the impact of supplementation. These include several trials in patients with adenomatous polyps of the colon, a precursor lesion for colon cancer. The authors interviewed 255 women who underwent colonoscopy at Columbia Presbyterian Medical Center between 1983 and 1985 with a telephone-administered structured questionnaire. Eleven interviews were excluded for various reasons. Overall, 57.7 percent of the 244 interviewees used vitamin pills on a regular basis (at least once a week for a year); 6.6 percent of the interviewees used vitamin A, 20.7 percent used vitamin C, and 16.2 percent used vitamin E. There were no statistically significant differences in vitamin usage among women with adenomatous polyps of the colon (105 cases), women with colon cancer (56 cases), and women without colonic neoplasia (83 cases). Despite widespread use of supplementary vitamins, this study failed to demonstrate major benefits in preventing colon polyps or cancer. Read in part at the Tenth Meeting of the American Society for Preventive Oncology, Bethesda, Maryland, March 7, 1986. Supported by NCI Grant No.CA37196, an American Cancer Society Junior Faculty Fellowship (AIN), a grant from the Andrew Mellon Foundation, and an internship from the Health Research Training Program of the NYC Department of Health (CMJ).     

Supplementation of dietary vitamins,protein and probiotics on semen traits and immunohistochemical study of pituitary hormones in zinc-induced molted broiler breeders

The purpose of this study was to investigate the effect of dietary vitamin E and vitamin C, probiotics mixture and protein level and their combination on semen quality and immunohistochemical study of some pituitary hormones in male broiler breeders. One hundred and eighty male broiler breeders 65 weeks old were divided into six groups by completely randomized design. The birds were subjected to zinc-induced molt by mixing zinc oxide at the rate of 3000 mg/kg in the feed. After molting, one group was fed control diet (CP16%). The other groups were fed vitamin E (100 IU/kg), vitamin C (500 IU/kg), probiotics (50 mg/L of drinking water), protein (CP14%) and combination of these components. These treatments were given for five weeks. After the feeding period, semen samples were taken and analyzed for semen volume, sperm concentration, motility and dead sperm percentage. Pituitary samples were collected from three birds per replicate and were processed for immunohistochemical study. The results of semen quality parameters revealed that semen volume and sperm motility were significantly high in the vitamin E fed group, while the dead sperm percentage decreased significantly in the vitamin C group. The morphometric analysis revealed that compared to other groups, vitamin E caused a significant increase in the size and area of FSH, LH gonadotropes and lactotropes. These results showed that vitamin E alone may play some role in the enhancement of semen quality and growth of gonadotropes and lactotropes.     

The Role of Homocysteine‐Lowering B‐Vitamins in the Primary Prevention of Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of mortality in the Western world. The effort of research should aim at the primary prevention of CVD. Alongside statin therapy, which is maintained to be an effective method of CVD prevention, there are alternative methods such as vitamin B substitution therapy with folic acid (FA), and vitamins B₁₂ and B₆. B‐vitamins may inhibit atherogenesis by decreasing the plasma level of homocysteine (Hcy)—a suspected etiological factor for atherosclerosis—and by other mechanisms, primarily through their antioxidant properties. Although Hcy‐lowering vitamin trials have failed to demonstrate beneficial effects of B‐vitamins in the prevention of CVD, a meta‐analysis and stratification of a number of large vitamin trials have suggested their effectiveness in cardiovascular prevention (CVP) in some aspects. Furthermore, interpretation of the results from these large vitamin trials has been troubled by statin/aspirin therapy, which was applied along with the vitamin substitution, and FA fortification, both of which obscured the separate effects of vitamins in CVP. Recent research results have accentuated a new approach to vitamin therapy for CVP. Studies undertaken with the aim of primary prevention have shown that vitamin B substitution may be effective in the primary prevention of CVD and may also be an option in the secondary prevention of disease if statin therapy is accompanied by serious adverse effects. Further investigations are needed to determine the validity of vitamin substitution therapy before its introduction in the protocol of CVD prevention.     

Vitamins and iron blood biomarkers are associated with blood pressure levels in European adolescents. The HELENA study

ObjectivesPrevious research showed that low concentration of biomarkers in the blood during adolescence (i.e., iron status; retinol; and vitamins B₆, B₁₂, C, and D) may be involved in the early stages of development of many chronic diseases, such as hypertension. The aim was to evaluate if iron biomarkers and vitamins in the blood are associated with blood pressure in European adolescents.MethodsParticipants from the Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional study (N = 1089; 12.5–17.5 y; 580 girls) were selected by complex sampling. Multilevel linear regression models examined the associations between iron biomarkers and vitamins in the blood and blood pressure; the analyses were stratified by sex and adjusted for contextual and individual potential confounders.ResultsA positive association was found in girls between RBC folate concentration and systolic blood pressure (SBP) (β = 3.19; 95% confidence interval [CI], 0.61–5.77), although no association between the vitamin serum biomarkers concentrations and diastolic blood pressure (DBP) was found. In boys, retinol was positively associated with DBP (β = 3.84; 95% CI, 0.51–7.17) and vitamin B₆ was positively associated with SBP (β = 3.82; 95% CI, 1.46–6.18). In contrast, holotranscobalamin was inversely associated with SBP (β = −3.74; 95% CI, −7.28 to −0.21).ConclusionsLevels of RBC folate and vitamin B₆ in blood may affect BP in adolescents. In this context, programs aimed at avoiding high BP levels should promote healthy eating behavior by focusing on the promotion of vegetable proteins and foods rich in vitamin B₁₂ (i.e., white meat and eggs), which may help to achieve BP blood control in adolescents.     

腹腔感染后维生素A、E、C代谢障碍的防治

目的观察完全胃肠外营养(TPN)添加维生素A、E、C对腹腔感染后抗氧化能力的影响。方法采用盲肠结扎加穿孔(CLP)模型,将SD大鼠随机分为对照组(CLP TPN)、治疗组(CLP TPN 维生素A、E、C)、延迟治疗组(CLP TPN 延迟应用维生素A、E、C),于术后当天以及第1、3、5天观察血浆及肝组织中维生素含量及丙二醛(MDA)、还原型谷胱甘肽(GSH)的变化。结果 CLP对照组维生素A、E、 C及GSH明显低于正常对照,MDA显著高于正常对照;治疗组和延迟治疗组维生素A、E、C及GSH显著高于对照组,但延迟治疗组低于治疗组;治疗组和延迟治疗组MDA明显低于对照组,但延迟治疗组高于治疗组。结论 TPN添加维生素A、E、C能改善腹腔感染后机体的抗氧化能力,减轻脂质过氧化损伤。     

孕妇维生素营养状况与胎儿生长发育的典型相关研究

目的 对孕妇维生素营养状况与胎儿生长发育的关系进行典型相关分析。方法 以湖南省长沙市224名孕妇为调查对象,测定了不同孕龄孕妇的血清维生素水平及胎儿生长发育评价指标,并对孕妇的膳食营养素摄入、生活因素进行了调查。结果 孕妇血清维生素E水平随妊娠进展明显上升,叶酸水平则下降,在孕晚期尤为明显;典型相关分析的结果显示:孕妇的4项血清维生素水平与孕妇产前宫高、腹围、胎儿股骨长、新生儿出生体重、新生儿Apgar评分5项指标呈正相关(P<0.05),提示孕妇维生素营养状况影响胎儿骨骼、肌肉、神经等的发育;对孕妇生活因素、膳食摄入进行综合分析的结果显示它们对胎儿生长发育的影响依次为孕妇的膳食援入(决定系数R~2=49.10％)、孕妇4种血清维生素水平(R~2=29.94％)、生活因素(R~2=14.32%)。结论 孕妇维生素营养状况与胎儿生长发育密切相关。